Fields, L., & Garruto, M. (2009).
Optimizing linked perceptual class formation and transfer of function.
Journal of the Experimental Analysis of Behavior, 91, 225-251.
A linked perceptual class consists of two distinct perceptual classes, A9 and B9, the members of which
have become related to each other. For example, a linked perceptual class might be composed of many
pictures of a woman (one perceptual class) and the sounds of that woman’s voice (the other perceptual
class). In this case, any sound of the womanÕs voice would occasion the selection of any picture of the
woman and vice versa. In addition, after learning to name the woman in the presence of one picture,
that name would be uttered when presented with all of the images of the woman’s face and all of the
sounds of her voice. This study involved 15 participants and sought to (a) maximize the percentage of
participants who formed linked perceptual classes, and (b) determine whether those classes acted as
transfer networks, that is, whether the discriminative function of one class member would generalize to
other members of the class and not to members of a different class. The rate of emergence of each
linked perceptual class was maximized by establishing a single class-linking conditional relation between
the clearest member of one class used as a sample stimulus and the most ambiguous member of the
other class used as a comparison stimulus. Class formation was demonstrated using the serial and
programmed presentation of A9ÐB9 probes that consisted of untrained pairs of stimuli drawn from the
A9 and B9 classes. Most participants showed immediate emergence of the two linked perceptual classes.
The remaining participants showed delayed emergence following a second exposure to each originally
error-producing probes. Once the linked perceptual classes had emerged, a differential response to a
specific member of one perceptual class generalized mostly or completely to the other members of that
linked class and rarely, if ever, to members of the other linked class. Thus, generalization did not
depend on the specific class members that had been used for discrimination training.
Key words: linked perceptual classes, generalized equivalence classes, response transfer, generalization,
delayed and immediate emergence, function-transfer networks, keyboard responses, humans